A Study of Siblings of Individuals with ASD: Comparison of Pragmatic Language Ability
Kang, V., Levesque, K., Anderson, A., Kresse, A., Faja, S., Neuhaus, E., Bernier, R., Webb, S. J.
Department of Psychiatry and Behavioral Sciences, University of Washington, Center on Human Development and Disabilities, University of Washington
Seattle Children’s Research Institute, Center for Child Health, Behavior, and Development
Background
Results
PRS Sum of Scores
*
N = 13 (M = 10, F = 3)
N = 13 (M = 7, F = 6)
MZ/DZ
MZ = 4, DZ =9
MZ = 10, DZ =3
MZ = 6, DZ =7
Verbal IQ
M = 116.31,
SD = 13.94
M = 101.00,
SD = 10.01
M = 117.46,
SD = 9.13
M = 10.02,
SD = 2.93
M = 10.50,
SD = 3.89
M = 10.40,
SD = 2.31
Procedure:
Subjects completed the Wechsler
Abbreviated Scale of Intelligence
(WASI) and a 15-20 minute interview
from the Autism Diagnostic
Observation Schedule (ADOS). The
interview from the ADOS was videorecorded, and the videos were later
rated by coders blind to diagnosis.
Coders assessed subjects’ pragmatic
language using the Pragmatic Rating
Scale-Modified (PRS-M) (Ruser, 2007).
Table 2 shows three of the four
subdomains in the PRS-M.
5
0
ASD Twin of ASD
TD Twin of ASD
Groups by Diagnosis
TD Twin of TD
*
5
4
3
2
1
0
ASD Twin of ASD
TD Twin of ASD
Groups by Diagnosis
TD Twin of TD
Does PRS Sum of Scores for a twin predict PRS Sum of Scores for the other?
18.00
16.00
R² = 0.6882
14.00
12.00
TD twin of ASD
10.00
ASD twin of ASD
8.00
4.00
TD twin of TD
R² = 0.0516
Linear (TD twin of ASD)
R² = 0.815
Linear (ASD twin of ASD)
2.00
-2.00
3.00
8.00
PRS Sum TW2
13.00
18.00
Linear (TD twin of TD)
High (poor) score on PRS Sum of a twin significantly predicted a high (poor) score on PRS Sum
for his or her twin in ASD concordant twin pairs, p = .011 and in TD concordant twin pairs,
p = .00, but not in the disconcordant pairs.
Does PRS Language Subscale Score for a twin predict PRS Language Subscale
Score for the other?
Image 1 Participant during ADOS interview
Emotional expressiveness and
awareness of the
other
Communicative
performance
Language
Direct emotional verbal
expression
Intonation
Indirect emotional verbal
expression
Descriptive gestures
Failure to reference
Emphatic gestures
Reformulation
Facial expressions
Eye contact
Mispronunciation
Grammatical errors
7.00
6.00
3.00
Table 2 Items and subscales of Pragmatic Rating Scale – Modified (PRS-M) (Ruser, 2007)
ASD twin of ASD
R² = 0.025
4.00
TD twin of TD
R² = 0.1698
Linear (TD twin of ASD)
2.00
0.00
0.00
Empathy
TD twin of ASD
5.00
1.00
Confusing accounts
10.00
R² = 0.0302
Linear (ASD twin of ASD)
R² = 0.362
1.00
2.00
3.00
PRS Language TW2
Linear (TD twin of TD)
4.00
5.00
6.00
High (poor) score on PRS Language Subscale of a twin significantly predicted a high (poor)
score on PRS Language Subscale for his or her twin in TD concordant twin pairs, p = .030,
but not in other pairs.
Linear (TD twin of ASD)
8.00
Linear (ASD twin of ASD)
R² = 0.3822
6.00
Linear (TD twin of TD)
40.00
50.00
60.00
70.00
SRS Total Score TW2
80.00
90.00
Does Vineland Communication Score of a twin predict PRS Sum of Scores for
the other?
R² = 0.0432
TD twin of ASD
13.00
ASD twin of ASD
11.00
TD twin of TD
9.00
R² = 0.0004
R² = 0.26
Linear (TD twin of ASD)
Linear (ASD twin of ASD)
7.00
5.00
55.00
Multiple regression analysis was used to test if three different social communication
measures of one twin significantly predicted the PRS scores of the other.
6.00
TD twin of TD
15.00
Do the social communication measures of one twin predict the pragmatic
language abilities of the other?
Table 1 Participant profile
12.00
High (poor) score on SRS Total of a twin with ASD significantly predicted a high (poor) score
on PRS Sum for his or her TD twin in disconcordant twin pairs, p = .014, but not in the the TD
concordant and ASD concordant pairs.
PRS Sum TW1
PRS Language Subscale
Score
*
TD twin of ASD
ASD twin of ASD
4.00
30.00
PRS Language Subscale Scores
PRS Language TW1
Age (in years)
10
R² = 0.0106
14.00
17.00
PRS Sum TW1
N = 13 (M = 5, F = 8)
15
TD twin of ASD group scored significantly higher (worse) than TD twin of TD group, p = .05,
and did not differ from ASD twin of ASD group. TD twin of TD group scored significantly lower
(better) than ASD twin of ASD group, p = .022.
Participants: Three groups of individuals participated in this study along with
their twin: (1) Typically developing children whose twin has a diagnosis of ASD
(TD twin of ASD), (2) Typically developing children whose twin is also typically
developing (TD twin of TD) and (3) Children with a diagnosis of ASD whose twin
also has an ASD diagnosis (ASD twin of ASD). All groups matched on age and
Nonverbal IQ.
Gender
*
TD twin of ASD group scored significantly lower (better) than ASD twin of ASD group, p = .02,
and did not differ from TD twin of TD group. ASD twin of ASD group scored significantly higher
(worse) than TD twin of TD, p = .013.
• We hypothesize that TD children from ASD disconcordant twin pairs will
perform better than children with ASD from ASD concordant twin pairs, but not
as well as TD children from concordant TD twin pairs. We also hypothesize that
the social skills of a twin will significantly predict the pragmatic language ability
of his or her other twin.
Methods
20
16.00
PRS Sum TW1
Overall Pragmatic Language Scores
• This study compared the pragmatic language ability between three groups: (1)
Typically developing (TD) children whose twin has a diagnosis of ASD (TD twin
of ASD), (2) TD children whose twin is also TD (TD twin of TD) and (3) Children
with a diagnosis of ASD whose twin also has an ASD diagnosis (ASD twin of ASD).
This study also looked at whether children’s pragmatic language ability can be
predicted by other social communication measures of their twin.
TD Twin of TD
18.00
Univariate Analysis of Covariance was used to test if the three groups significantly
differ on their pragmatic language. Verbal IQ was considered as the Covariate.
• Deficits in pragmatic language are also observed in siblings of individuals with
ASD, thus it has been hypothesized that pragmatic language may be part of the
broader autism phenotype (BAP) (Bishop, 1997; Baron-Cohen, 1988).
ASD Twin of ASD
Does SRS Score of a twin predict PRS Sum of Scores for the other?
Comparison of Pragmatic Language Across Different Diagnostic Groups
• Previous studies have found impairment in pragmatic language across
individuals with Autism Spectrum Disorder (ASD) (Tager-Flusberg et al., 2005;
Baron-Cohen, 1988; Bishop et al., 2006). Impairment in pragmatic language
includes overtalkativeness, talking in a stereotypical manner, or being unable to
consider others’ viewpoints (Bishop et al., 2006).
TD Twin of ASD
Results Cont.
Linear (TD twin of TD)
65.00
75.00
85.00
95.00
105.00
Vineland Communication Score TW2
115.00
Low (poor) score on Vineland Communication Subscale of a twin with ASD marginally
significantly predicted a high (poor) score on PRS Sum for his or her TD twin in disconcordant
twin pairs, p = .075, but not in the TD concordant and ASD concordant pairs.
Summary and Conclusions
Summary
• TD twins of children with ASD performed more similarly to TD twins of TD children in all
areas of pragmatic language except for the language subscale, which includes grammar,
reformulation, pronunciation and content clarity (GRPC). In the language subscale, TD twins of
children with ASD performed more similarly to children with ASD. This could suggest that
individual diagnosis matters in the development of pragmatic language ability, except for the
language subscale, where level of GRPC in a TD child is influenced by the diagnosis of his or her
twin with ASD. This could suggest a potential presence of broader autism phenotype (BAP) in
the development of GRPC in TD twins of children with ASD.
• To learn more how the social communication ability of TD children are related to the social
communication ability of their twins with ASD, a correlational analysis was done between the
social communication measure of the children with ASD and the pragmatic language ability of
their TD twins. Poor overall pragmatic language ability of TD twin was predicted by the poor
SRS Sum of Scores and Vineland Communication Score of his or her twin with ASD, despite the
disconcordant diagnosis. This suggests that the development of pragmatic language ability in
TD twins of children with ASD could be predicted by some measures of social communication
ability of their twins with ASD.
• When looking at the relationship between the pragmatic language ability of a TD child and of
his or her twin with ASD, there was no significant correlation. However, for the concordant twin
pairs (ASD-ASD and TD-TD), the pragmatic language ability of a twin predicted his or her other
twin’s pragmatic language ability.
Limitations and future directions
•Participants were not matched on twin pair gender or zygosity. Future studies should
investigate if these trends differ between male, female, and discordant sex twins.
• Considering that fraternal twins share greater amount of environmental factors than non-twin
siblings, future studies should include an additional sibling group to help in teasing apart the
roles of genetics from the environment.
References
Baron-Cohen, S. (1988). Social and Pragmatic Deficits in Autism: Cognitive or Affective? Journal of Autism and Developmental
Disorders, 18(3), 379-402.
Bishop, D. M. (1997). Uncommon Understanding: Development and Disorders of Language Comprehension in Children.
Psychology Press/Erlbaum (UK) Taylor & Francis, 277(8).
Bishop, S. L., & Lord, C. (2006). Autism Spectrum Disorders. New York, NY, US: Guilford Press.
Ruser, T. F., Arin, D., Dowd, M., Putnam, S., Winklosky, B., Rosen-Sheidley, B., … Folstein, S. (2007). Communicative
Competence in Parents of Children with Autism and Parents of Children with Specific Language Impairment.
Journal of Autism Development and Disorder, 37, 1323-1336.
Tager-Flusberg, H., Paul, R., & Lord, C. (2005) Language and Communication in Autism. Development and Behavior, 12,
335-364.
Acknowledgment
This study was funded by Autism Speaks Foundation, Autism Science Foundation Undergraduate Summer Research
Fellowship, and UW Undergraduate Research Conference Travel Award.
This poster was presented at the International Meeting for Autism Research and the UW Undergraduate Research Symposium on May 15, 2015 and the UW Psychology Honors Festival on May 19, 2015 . Contact: kangv@uw.edu